Because of their low-profile designs, light weights, and low power consumption, liquid crystal display devices are widely used in display instruments, such as television sets, personal computers, and PDAs. In particular, as exemplified by liquid crystal display devices for television sets, the sizes of liquid crystal display devices are rapidly increasing. In order to increase their sizes, a multi-domain vertical alignment (MVA) mode is suitably used because this mode can give a high yield even for a large display area and realize a wide viewing angle. In the multi-domain vertical alignment mode, when no voltage is applied to a liquid crystal layer, liquid crystal molecules are vertically aligned on a substrate face. Thus, the multi-domain vertical alignment mode can produce a higher contrast ratio than the known twisted nematic (TN) mode.
However, the MVA mode employs ribs (projections), which reduce the aperture ratio and consequently reduce white luminance. Although the intervals of the ribs may be increased to overcome this disadvantage, a decrease in the number of ribs, which are alignment regulating structures, increases the time required to stabilize alignment upon the application of a voltage to the liquid crystals. This causes a problem of a low response speed. In order to dissolve such a problem and realize high luminance and high-speed response, a technique for providing a pretilt angle using a polymer (hereinafter also referred to as a polymer sustained alignment (PSA: alignment sustaining) technique) has been proposed (for example, Patent Literature 1). In accordance with the PSA technique, a liquid crystal composition that contains liquid crystals and a polymerizable component, such as a monomer or an oligomer (hereinafter referred to as a “monomer etc.”), is charged between substrates. While a voltage 1 is applied between the substrates to incline liquid crystal molecules, the monomer etc. is polymerized to form a polymer layer. Even after the voltage application is stopped, the liquid crystals can have a predetermined pretilt angle, thereby regulating the liquid crystal alignment direction. The monomer etc. is polymerized by heat or light (ultraviolet light) irradiation. Use of the PSA technique obviates the necessity for ribs, increases the aperture ratio, and increases the speed of response because of a pretilt angle of less than 90 degrees throughout the display area.